Profiling Players in the WTA

As most readers will know, all Tennis players are far from equal. Obviously some players are better than others, and generally this information is well processed by the betting markets, hence why it is difficult to beat major bookmakers by more than a few percent return on investment.

However, all players who appear equal may not be necessarily so. Some players will have a higher top level than similarly ranked opponents, but may struggle with consistency against worse players, and this information is unlikely to be as well known to the markets.

There are various metrics that we can look at for profiling players which creates various entry points both in the pre-match and in-play markets, as well as outright markets. Would you really be keen to back a player to win the tournament if they have to play three top 20 players and their win rate against top 20 players is less than 20%? If a player with an atrocious record against a top 10 opponent is a set up, or even a set and break up, they can be opposed in the knowledge that they've been unable to see out these winning positions in the past.

CASE STUDY 1 - PETRA KVITOVA:-

A good example of the discrepancy mentioned above is Petra Kvitova. The Czech has one of the best records in the WTA against top 10 opposition (which is illustrated later in the article) with a 51.9% career win rate. This rockets up to 78.8% against ranks 21-50, but falls to 73.8% against ranks 51-100, despite the average WTA player improving their win rate by a ratio of 1.16 against ranks 51-100 compared to ranks 21-50 or an average improvement of 8.6%. Based on that ratio, her win rate against ranks 51-100 should increase to 91.4% or by average improvement should rise to 87.4%. Either way, she is significantly underperforming against much worse opponents.

Petra Kvitova's performances against much worse opposition are significantly worse than expectation...

CASE STUDY 2 - SLOANE STEPHENS:-

The American prospect has a very poor 4-26 record against top 10 opponents in her career. This undoubtedly is a very strong factor towards why she had to wait so long to win her maiden WTA title, when similarly aged players perceived to be worse than her had beaten her to it. Indeed, her win in Washington didn't even feature a victory against a top 20 player (highest win vs Stosur, rank 23) and only two wins were against top 50 opponents. It's difficult to give her too much credit for this. She also fits nicely into the above bracket of not being able to see out winning positions - in these 30 matches against top 10 opponents she onlyconverted four of her nine first set wins into victories.

I assessed the career records for all current WTA players with a reasonable sample of matches. Below are the best WTA players against top 10 opponents (minimum 15 career matches against top 10 opponents):-

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs top 10

Matches

Wins

Win %

Overall

2876

921

32.0

Williams S

103

81

78.6

Bencic

16

10

62.5

Sharapova

87

52

59.8

Cetkovska

17

9

52.9

Kvitova

77

40

51.9

Azarenka

103

53

51.5

These six players were the only WTA players able to boast better than a 50% win rate against top 10 opponents, a number which may surprise some readers.

It's absolutely no surprise to see Serena Williams overwhelmingly better than her peers here, but it's interesting to note that the richly talented Swiss prospect, Belinda Bencic, is second from a relatively small sample. This bodes very well for her career progression. Apart from Petra Cetkovska, whose inclusion appears very random (and again is from a smaller sample), the likes of Williams, Sharapova, Kvitova and Azarenka are players who have been at the top of the WTA for long periods of time and their records against top 10 opponents reflect that.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs top 10

Matches

Wins

Win %

Overall

2876

921

32.0

Flipkens

21

3

14.3

Koukalova

35

5

14.3

Strycova

28

4

14.3

Stephens

30

4

13.3

Watson

16

2

12.5

Gajdosova

25

3

12.0

Hercog

18

2

11.1

Niculescu

26

2

7.7

Govortsova

18

1

5.6

Dellacqua

15

0

0.0

The table above shows the worst players in the WTA against top 10 opponents (again, a minimum of 15 matches were required - which filtered out many other poor performers). These players are likely to be unable to have a relatively consistent level, or in particular, a peak level that can be maintained in matches against the elite.

CASE STUDY 3 - CASEY DELLACQUA

Casey Dellacqua's record against top 10 opposition is horrific...

As seen in the table above, Dellacqua is 0-15 against top 10 opponents in her career. However, that only tells part of the story. She's actually only won one set in those 15 matches - against Angelique Kerber in Beijing in 2014. Pretty much whatever the circumstances she should be opposed in these scenarios, particularly if she is leading/trading shorter than SP.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs top 20

Matches

Wins

Win %

Overall

5398

1978

36.6

Williams S

163

134

82.2

Sharapova

141

92

65.2

Azarenka

155

92

59.4

Wozniacki

157

91

58.0

Williams V

100

55

55.0

Muguruza

60

32

53.3

Halep

96

51

53.1

Kvitova

132

70

53.0

Against top 20 opposition, several new players are able to boost their win percentage to over 50%. Caroline Wozniacki in particular saw her win rate improve strongly, indicating that she has issues against the top players in the WTA, but is considerably better than second tier opponents. Venus Williams, Garbine Muguruza (who was very close to inclusion in the best players against top 10 opponents) and Simona Halep are also included, whilst the small samples of Bencic and Cetkovska drop to below 50% here.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs top 20

Matches

Wins

Win %

Overall

5398

1978

36.6

Arruabarrena

15

2

13.3

Knapp

23

3

13.0

Zhang S

24

3

12.5

Niculescu

48

6

12.5

Babos

18

2

11.1

Bertens

18

2

11.1

Govortsova

38

4

10.5

Soler-Espinosa

24

2

8.3

Dominguez Lino

30

2

6.7

Nara

17

1

5.9

Hsieh

23

1

4.3

With some bigger samples, some of the poor performers against top 10 players who were eliminated due to sample size issues are now included. Su-Wei Hsieh and Kurumi Nara in particular have struggled very badly against top 20 opponents whilst the Spanish duo of Silvia Soler-Espinosa and Lourdes Dominguez Lino have fared little better. Monica Niculescu is an interesting inclusion, given her win rate overall isn't that bad. It would appear her unorthodox style does not match up well against better players.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs 21-50

Matches

Wins

Win %

Overall

6183

3247

52.5

Williams S

115

102

88.7

Sharapova

106

92

86.8

Azarenka

117

95

81.2

Kvitova

132

104

78.8

Williams V

74

53

71.6

Wozniacki

183

129

70.5

Radwanska A

165

116

70.3

Against a slightly lower calibre of player - the 21-50 rank bracket - the usual suspects are again at the pinnacle. Agnieszka Radwanska sneaks into the over 70% subset, indicating that she is a scaled down version of Wozniacki - able to beat the 21-50 rank players but struggles against better. 37 players had a win percentage of 50% or above, and interestingly the trio of Svetlana Kuznetsova, Sam Stosur and Andrea Petkovic were just a few percent off making this list. Some other names worthy of mention here were the teenage prospect Ana Konjuh, whose 58.8% was well above average, as well as Yaroslava Shvedova, Julia Goerges and Kiki Bertens - all relatively mediocre players who had a win percentage of 50% or greater against rank 21-50.

It's also worth noting that players perceived to be relatively decent - Alize Cornet (43.4%), Eugenie Bouchard (41.9%), Camila Giorgi (41.5%) and Caroline Garcia (38.2%) - were well below average in this area, although not nearly as bad as the other names on the list below:-

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs 21-50

Matches

Wins

Win %

Overall

6183

3247

52.5

Larsson

65

19

29.2

Arruabarrena

31

9

29.0

Zhang S

31

9

29.0

Tsurenko

38

11

28.9

Hradecka

53

15

28.3

Dominguez Lino

47

13

27.7

Lucic-Baroni

48

12

25.0

Pereira

16

4

25.0

Hlavackova

35

8

22.9

Zheng S

17

2

11.8

Lara Arrubarrena has a poor record against better players...

Again, the likes of Lara Arruabarrena, Shuai Zhang and Lourdes Dominguez Lino feature which is absolutely indicative that these players cannot compete well against better players on tour - it looks like they simply do not have a high enough top level in their locker. The Brazilian clay courter, Teliana Pereira, was filtered out due to sample size issues previously but has a big enough sample to merit inclusion here. I'd also bracket her with the previously mentioned trio who cannot raise their game.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs 51-100

Matches

Wins

Win %

Overall

7773

4748

61.1

Williams S

66

61

92.4

Williams V

71

64

90.1

Azarenka

90

80

88.9

Wozniacki

122

107

87.7

Sharapova

77

67

87.0

Radwanska A

111

96

86.5

Ivanovic

93

77

82.8

Jankovic

106

82

77.4

Stosur

95

73

76.8

The table above indicates the best players on tour when playing against the 51-100 ranking bracket. Again, the list comprises largely of the usual suspects, although Venus Williams' rise is extreme. The veteran trio of Ana Ivanovic, Jelena Jankovic and Sam Stosur beat the 75% cut-off for inclusion, indicating that they are likely to be 'flat-track bullies' - players that find it easy against poor opposition but struggle against better. As mentioned earlier, Kvitova's win percentage has dropped against this ranking bracket so she isn't included here.

CAREER STATS

CAREER STATS

CAREER STATS

Player

vs 51-100

Matches

Wins

Win %

Overall

7773

4748

61.1

Babos

56

24

42.9

Hlavackova

61

26

42.6

Voegele

108

46

42.6

Bertens

67

28

41.8

Pereira

29

12

41.4

Tsurenko

85

34

40.0

Tomljanovic

51

19

37.3

Zheng S

34

12

35.3

Rogers

29

10

34.5

The above players had the worst records against rank 51-100 opponents. Again Pereira is included, as well as Babos, Tsurenko and Saisai Zheng, who were also included in previous poor performing categories. It would seem that this quartet derive a high percentage of their wins against non-top 100 opposition.

It's very unlikely that the likes of Teliana Pereira can improve their ranking signficantly given her poor record against better opponents...

Finally, we can look at which players perform very well against rank 51-100 players compared to against better opponents. The following players led the table for 'win % vs rank 51-100 - win % vs rank 1-50':-

Win % vs 51-100 - 1-50

Player

Difference

Overall

15.97

Jovanovski

37.18

Peng

36.71

Lepchenko

33.14

Svitolina

32.81

Bouchard

31.09

McHale

30.80

Larsson

30.47

Hsieh

29.86

Ivanovic

29.20

Wickmayer

29.13

Kovinic

29.06

Bacsinszky

28.75

Williams V

28.07

The players listed above have excellent records against the lower end of players on tour and may well be able to make decent impacts in some of the lower International level events on tour, which generally comprise of many players from this ranking bracket. The likes of Jovanovski and Svitolina in particular have claimed titles in the likes of the Baku International, which traditionally features very weak fields, whilst Venus Williams has made the effort to travel to low-level events in Florianopolis and Quebec City in recent times in an attempt to claim titles. These players are also likely to fall into the 'flat-track bully' category.

Conversely, the following players performed below expectation based on the above formula:-

Win % vs 51-100 - 1-50

Player

Difference

Overall

15.97

Tsurenko

8.97

Halep

8.08

Kvitova

7.92

Williams S

7.53

Rogers

7.21

Muguruza

6.54

Cetkovska

5.51

Tomljanovic

5.44

Bertens

4.29

Unsurprisingly based on the previous stats mentioned, Kvitova made the list whilst fellow top ten players Simona Halep, Serena Williams and Garbine Muguruza also were included. Williams' poor increase can be disregarded, as the average win percentage increase of 15.97% would give her a win percentage over 100% - effectively she cannot improve significantly on already magnificent figures!

Kiki Bertens was the worst player using this metric and she does strike me as a player with a high potential level (particularly on clay) with a mediocre average/poor low level. Backing this up, the Dutchwoman has a career ROI of 14.4% as an underdog based on Pinnacle closing prices and 32.0% as a 3.00+ underdog.

Overall, we can use all the information in this article in various ways.

With knowledge of player's tendencies against various levels of opposition we can assess how they are likely to perform in future matches - if a player has not been able to beat top 20 players with any regularity halfway through their career it is extremely unlikely they will be able to resolve this issue. In addition to this, we can also see that the nine players listed above have pretty much no chance of ever winning a WTA main draw tournament apart from those with very weak fields (e.g. Baku/Rio). Basing outright positions on hold/break percentages and ranking bracket percentages (considering the tournament field/draw) is likely to yield very strong returns.

In addition to this, if a player has a poor record against better opponents but is leading in-play, they can be opposed at shorter prices particularly if they have a low projected hold for the match-up, and/or they are vulnerable at retaining leads (or their opponent is strong at recovering deficits).

The Lead Loss/Recovery Data Spreadsheets have taken the Tennis Trading World by storm - discussed in detail in October 2015 at the Matchbook Traders Conference these incredible spreadsheets highlight lead loss & deficit recovery in individual sets, as well as how often a player loses/gains the first break of the second set based on whether they won or lost the first set!